Engineering
United States Department of Agriculture
Forest Service
Technology &
Development Program
December 2002
7100
0271-2333–MTDC
Bar-Code Tracking Systems Overview
Jasen Neese, Project Assistant, and Kathleen Snodgrass, Project Leader
I
s that pile of paper signout sheets driving you nuts?
Are you spending days compiling information for
mandatory equipment or hazardous materials reports?
Perhaps you should consider implementing a tracking
system based on bar codes.
This report will help you decide whether moving to a
bar code-based system would be worth the trouble of
setting up such a system. You should investigate bar
coding if you have large quantities or many varieties of
material that must be tracked, inventoried, secured, or
reported. Such materials might include tree-marking
paint, recreational passes, or firefighting equipment.
Possible uses include:
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Stumpage tracking
Pesticide use reporting
Chemical tracking
Road and trail inventory
Real-property inventory
Connecting hard copies of maps (such as maps of
old growth) to the corresponding resource database
Vehicle or equipment checkout systems
Tracking sales of interpretive items
Forest resource inventories
Fuel tracking
Document and file inventories
Publication shipping
Using a bar-coding system to track items involves printing
and attaching labels to the items, scanning the labels,
entering the updated information into a computer, and
using software to track and run reports on the inventory.
At the heart of each bar-coding system is the unique
identification (ID) number assigned to every item being
tracked. An ID number (in the form of a bar-code label)
is attached to each item in the inventory. When a labeled
item is moved, shipped, used, disposed of, or modified
in any way that should be recorded, the item’s bar code
is scanned and the information goes into the information
tracking system.
Most data storage programs are databases that function
like electronic filing cabinets. When you scan a bar code,
you are removing that item’s individual file from the file
cabinet and opening it. Information can be changed,
How a Bar-Code System Works
Bar-code scanning (figure 1) is familiar to nearly everyone
because scanners are used at most supermarket
checkout counters. Bar coding is useful for far more than
identifying the cost of a loaf of bread.
Figure 1—The laser scanner is the preferred tool of inventory and
shipping managers.
For additional information, contact: Kathie Snodgrass, Project Leader, USDA Forest Service, MTDC; 5785 Hwy. 10 West; Missoula,
MT 59808–9361. Phone: 406–329–3922; fax: 406–329–3719; e-mail: ksnodgrass@fs.fed.us
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added, or analyzed and the file can be put back into the
filing cabinet. You can use databases to find a specific
item or to print inventory reports, use statements (reporting
the amount of materials such as pesticides that have
been used), or disposal records. Databases help you
locate and retrieve relevant information in a quick and
efficient manner.
Here’s a brief example showing how a bar-code system
could expedite a unit’s work:
A ranger station has a supply of GPS (global positioning
system) receivers used for various forest inventory and
mapping projects. Each receiver is assigned a unique
bar code. A bar-code label is attached to the back of the
receiver. When employees take a GPS receiver out for
the day, they scan its bar code. A description of the
receiver is displayed on the computer attached to the
scanner. Employees enter the date, their name, and
the work project. They save the information and take
the receiver. Check-in procedures are similar. Later in
the field season, one of the receivers is found to be malfunctioning and is reporting slightly skewed positioning
data. The district needs to know which projects may have
been affected. Using the bar-code system, a list of those
projects can be produced in just a few minutes. If the
district had relied on the customary paper checkout
system, that information would have taken most of a
day to obtain.
create high-, medium-, and low-density bar codes, compatibility with numerous hardware and software packages,
and widespread product and software support.
Bar codes can be printed in different densities (figure 2).
Density describes how closely the vertical lines are
spaced. High-density label lines are closely spaced. Lowdensity lines are spread farther apart. Some types of
scanners cannot read high-density bar codes. Low-density
bar codes are less affected by printing imperfections and
can be read more reliably, especially if the bar-code label
is damaged. However, low-density bar codes require
larger labels than medium- or high-density bar codes
with the same amount of information.
LOW DENSITY
MEDIUM DENSITY
HIGH DENSITY
Bar Codes
The series of vertical black lines and spaces known as
a bar code is a simple, compact, graphical way to record
data. A serial number, Chemical Abstract Service (CAS)
registry number, ID code, or other data can be turned
into a bar code using a set standard, called a symbology.
More than 250 bar-code symbologies are in use today.
The uniform product code (UPC) symbology used in the
retail industry is one type of symbology. POSTNET, used
by the U.S. Postal Service for encoding zip code and
address information, is another.
Bar-code symbology code 128 is recommended for Forest
Service use. Code 128 is the standard in the shipping
industry and is widely used in other areas. The advantages of code 128 include the ability to encode all 128
ASCII characters (lowercase and capital letters, numbers,
punctuation marks, and other symbols), the ability to
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Figure 2—Bar-code density is one of the factors that determine the
size of the bar-code label you should use.
Bar codes are read by scanners. Any newer commercially
available scanner has the ability to read most of the more
common types of bar-code symbologies. Software interprets the pattern of lines and spaces and stores the data
in formats that can be associated with other items,
retrieved, organized, and compiled into reports.
Basic Operation of an Inventory
System
Setup—Setup and the initial inventory entry are usually
the most time-consuming steps in using a bar-code
system. The basic procedure is:
❏ A bar code is assigned to each item.
Location or Tracking Feature—The most commonly
used addition to an inventory system is a description of
an item’s physical location. As items are added, deleted,
or moved, the bar code is scanned and the location
description is changed. Storage locations can also be
bar coded by placing a label on a door, cabinet, or adjoining wall. When workers move an item, they scan the item’s
bar code, then the new location’s bar code, automatically
updating the item’s location.
❏ All items and their associated attributes are entered
into the database by hand or imported from an existing
file, spreadsheet, or database.
❏ Bar-code labels are printed and all items are labeled
with the correct bar code.
Updating and Inventory—Periodic inventories are
needed to check the physical inventory against the data
stored in the software program. During an inventory, all
the bar-code-labeled items are scanned. The system
compares the inventoried amount onhand to the amount
that has been checked in and out during the inventory
period. Discrepancies can be investigated and corrected.
Receiving—When a new item is added to the system, a
unique bar code is assigned to the item and a matching
label is printed and attached. The bar code is scanned.
The software will display related information. The user
must enter the quantity received, a storage location,
materials safety data sheet (MSDS) number, and other
information into the database. When many similar items
are received, the software provides an easy way to copy
descriptions and coding.
Disposal—When a bar-coded container is emptied or
moved to another site, the item must be removed from
the inventory. Information on a disposed item is not
deleted—it is moved from the onhand inventory file to
a disposed of file. You can save the disposed of files
for as long as you wish so you can access that information
when completing reports or reviewing usage in past years.
Additional Features
The features that can be added to an inventory system
are almost endless.
Checkout Feature—Another common addition is known
as the pharmacy system. This checkout component keeps
track of who has used an item. Each user is assigned
a unique ID. When users remove something from the
inventory, they scan the item’s bar code, enter or scan
their ID, and enter information indicating where they are
taking the item, what it will be used for, when it will be
returned, and so forth, depending on tracking needs.
Automatic Ordering and Purchasing—This feature is
helpful for high-use items that run out of stock quickly.
An automatic system will electronically place an order
when the quantity of an item drops below a specified
level. A simpler version is an alert system that simply
notifies the user that supplies have dropped below a
predetermined level.
Distribution and Shipping—Publication libraries in
research facilities that have an active distribution system
may find a shipping component useful. The system can
track inventory and shipping costs, keep track of address
information and project codes, and print shipping labels.
Drawbacks of Bar-Code Systems
Bar-code systems can be expensive to acquire, especially
if preconfigured systems will not serve your needs. In
addition, bar-code systems can take enormous amounts
of time to set up if they must track large quantities of
different items. They require the use of electronic devices
and software that can confuse employees or be destroyed
if employees are not properly trained to use the systems.
Anyone contemplating using a bar-code system should
evaluate whether the system can realistically be expected
to pay for itself within a reasonable amount of time by
increasing productivity or reducing losses.
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Hypothetical Applications
The following applications could solve typical Forest
Service problems. If you’re thinking about using a barcode system, these examples might help you. These are
not actual installations. They are hypothetical solutions
based on real concerns and problems identified by Forest
Service employees.
Forest Tool Tracking: The Problem
A national forest had a significant amount of equipment
that was shared among the forest’s four districts for various
work projects. Equipment loaned or exchanged among
ranger districts and program areas was seldom returned
to its proper storage area. By the end of each field season,
a good deal of equipment was missing due to theft or loss.
After years of being unable to track who was responsible
for the missing equipment, regularly replacing missing
equipment, and losing valuable time and manpower while
locating misplaced equipment, the leadership team
decided something had to be done.
A Solution—A comprehensive, software-based, forestwide inventory checkout system was established based
on bar codes. The software is a powerful multiuser
version of a commercially available inventory-tracking
program used by small-scale warehouse and shipping
companies. The features of the commercial program
closely matched the requirements set out by the planning
committee.
Software and Communications—The main tracking
system resided on the server at the supervisor’s office.
Most stations were connected to the server by phone
lines. Copies of the master database resided on each
checkout computer, allowing checkout to proceed quickly.
Data updates were automatically transferred back to the
supervisor’s office and the updated forestwide inventory
was routed to all the checkout stations. A couple of the
equipment depots were not served by phone lines, so
high-gain directional antennas were installed to connect
them with the nearest ranger station.
Additional Uses, Updating, and Disposal—Anyone
with access to the server and a user ID could use the
program to locate equipment across the Forest. Access
to more advanced features such as report compiling,
depreciation accounting, and user tracking was limited
to certain employees. The software allowed authorized
users to transfer a piece of equipment’s storage location
from one checkout area to another. Annual offseason
inspections were done by scanning each item and comparing its location and amount counts to information in
the system. Items were scanned before disposal to keep
the inventory up to date.
Advantages and Problems—This tracking system was
not cheap, and some employees did not like having to
check all the major equipment in and out. However, the
forest found that the system paid for itself in reduced
equipment replacement within 2 years.
System Setup—The forest used the off season to
inventory equipment, assign bar-code IDs, attach labels,
and enter related information into the software program.
Every employee was issued a new Forest Service ID
card. On the back of the card was the employee’s unique
bar-code ID number.
Storage Areas and Checkout Procedures—Each
equipment storage area was equipped with a computer
loaded with the checkout software and an attached barcode scanner (figure 3). Certain stations were equipped
with bar-code printers for labeling new equipment and
replacing worn labels. To check out equipment, employees
scanned their ID bar codes, then the equipment’s bar
code. The electronic database recorded the equipment
transfer from its storage location into the care and responsibility of the employee. Employees used an identical
procedure when they returned the item. Depending on
the type of equipment, the user was prompted to enter
additional information such as the project name, location
where the item was used, and so forth.
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Figure 3—This scanner is attached to a
pulley with a steel cable. The scanner can
be moved in the storage area, but is less
likely to be lost or damaged.
Chemical and MSDS Inventorying: The Problem
A researcher in a Forest Service laboratory on a university campus used a minute amount of chemicals in her
projects. The university began requiring that she report
weekly the types of chemicals she bought, how much she
bought, and how much she used. In addition, she had to
provide the university with a copy of the corresponding
material safety data sheet any time she purchased a new
chemical. She was annoyed that a significant chunk of
her time was spent inventorying her small supply of lowtoxicity chemicals and providing MSDS forms to the
university. She had seen fellow researchers use a barcoding system to track laboratory experiment samples
and wondered if a similar system would simplify inventorying her chemicals and MSDS sheets. She was hesitant
about spending time and money on a bar-coding system
that might be just as burdensome as the reporting
requirements.
A Solution—The researcher purchased a low-cost barcode inventory package that included everything needed
for her small-scale operation. Her needs included:
❏ A software package to track purchase, use, and
disposal of chemicals
❏ Software to inventory her collection of MSDS sheets
and link them to the chemicals
❏ Software to design and print labels
❏ A label printer
❏ A supply of labels
contained. When she used a chemical, she scanned the
bar code and entered the quantity she used. When the
container was depleted, the system automatically recorded
the container as empty and moved the record to the
disposed of category. The software’s report-generating
capabilities made her chemical reporting to the university
a snap.
Problems—The canned inventory program would not
store and transfer MSDS sheets electronically. Purchasing
software with MSDS storing capabilities would have cost
twice as much. She decided to bar code the MSDS sheets
and link them to the appropriate chemicals in the database. This allowed her to inexpensively manage the
MSDS sheets with her chemicals. When she needed to
submit MSDS sheets to the university, she printed a list
of her current inventory of chemicals and their MSDS
numbers. She pulled the corresponding MSDS sheets
from her paper files and sent them to the administrators.
Pesticide Reporting: The Problem
A manager at a Forest Service nursery was required to
report pesticide usage annually to the Washington Office
and the State regulatory agency. His pesticide tracking
method was a paper signout sheet. He transferred information weekly to a database on his computer. Reports
took a long time to compile because all the information
had to be converted and composed into a standard narrative format. The manager wanted a quicker process.
However, he was concerned about employee resistance
to using a more complex system. The paper sheet method
worked fine, except for the time it took to transfer the
information from the paper into the database and the
trouble of compiling the data at report time.
❏ A bar-code scanner
After investigating various equipment from different
manufacturers, she decided to purchase a package that
included inventory and labeling software, a scanner, and
cable connections. She loaded the software on her computer. Her inkjet printer worked fine for printing paper
labels, because the labeling software supported her printer
and she had no need for durable synthetic labels that
would have required a special printer. She purchased
paper label blanks at the local office supply store.
System Setup—Setup was quick and easy because the
researcher had few chemicals to enter into the system.
System Use—Whenever the researcher received a new
chemical, she created a new bar code, labeled the
container, and created a description in the program that
included the type of chemical and how much the bottle
A Solution—Because the nursery already had barcoding software, printers, and scanners to track its nursery
stock and shipping operations, the manager decided to
use a bar-code-based inventory and checkout system.
The only additional components he needed were a datamanagement software program and a checkout system
for the pesticide storage shed (figure 4). The manager
and the nursery database administrator worked together
for a couple of weeks to develop a pesticide data management program using Microsoft Access.
The new database could supply a product-use report
(figure 5) at any time with a simple selection from a menu.
It also alerted the manager when pesticide amounts
dropped below the restock quantity and provided reports
listing pesticide use by each employee, total amounts
of each pesticide used, and total pesticides applied to a
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chose the cordless laser scanner because many of the
pesticides come in curved containers or bags and it was
a long way to the other end of the storage shed.
System Setup—It didn’t take long to inventory existing
chemicals and set up the system. Only a dozen different
pesticides are used at the nursery, but the quantities
are substantial.
System Use—The data-management program was
loaded on computers in the manager’s office and in the
storage shed. The storage shed computer displayed a
checkout screen that looked like the old paper checkout
sheet. To check out pesticides, employees scanned the
container’s bar code. The computer displayed the barcode ID and associated information such as the pesticide’s
Figure 4—Many Forest Service installations use storage units similar
to this one. Not all are as nicely organized and labeled.
FY 2001Pesticide Use Report
Prepared By:
Phone Number:
Date:
Region and Forest Code:
Administrative Unit Name:
Pesticide
Bruce Spruce
406.555.1285
9/15/01
R1 F606
Engelman N.F.
Common
Name
EPA
Registration
Number
2,4-D
Borax
Dazomet
Weedar 64
Sporax
Basamid
71368-1
2935-96-4
7969-99-51036
Glyphosate
Rodeo
Picloram
Tordon 22K
524-343
CAS:
002545-60-0
Number of
Acres
Treated
Application
Method
40 lbs.
3 lbs.
1050 lbs.
50
6
3
Ground Spraying
Ground Spraying
Ground Spraying
Noxious Weeds
Nematodes
Fungus
16 lbs.
20
Ground Spraying
Knapweed
Site Preparation
Site Preparation
Disease Control
Recreation
Improvement
881 lbs.
75
Ground Spraying
Noxious Weeds
Site Preparation
Quantity
Unit of
Measure
Target Pest
Management
Objective
Figure 5—The report feature of inventory software programs makes it much easier to meet reporting requirements.
specific crop or area. Custom reports could be created
using the query language in Access.
The nursery manager considered a checkout system
based on detachable bar-code labels. Employees would
use a hard-copy sheet similar to the one they were already
using to record their name, date, and the amount of
pesticide. They would remove a bar-code sticker from
the pesticide container and place it on the sheet (figure
6). The manager would still have to enter the information
from the checkout sheet into the database, but the annual
reporting would be a snap.
Instead, the manager chose a fully electronic checkout
system using a stand-alone computer workstation with
a cordless laser scanner. He decided that the time saved
by automatic data entry would more than offset the time
spent training employees to use the new system. He
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common name, its EPA (U.S. Environmental Protection
Agency) registration number, and its MSDS number. The
program prompted the user to enter required checkout
data. As pesticides were received, the information was
entered by the manager directly into his computer. Barcode labels were printed and attached before the materials
went into the storage shed.
Problems—Because there was no computer network
line to the storage shed, the manager regularly copied the
checkout database files from the storage shed computer
onto a floppy disk and loaded them onto his computer in
the main office. If a network or phone line could be run
to the storage shed or if a connection could be established
using wireless computer networking cards, data would
be automatically transferred into his system as employees
received or checked out pesticides.
Figure 6—A pesticide checkout sheet with attached bar-code labels.
More Information on Bar-Code Systems
Acknowledgments
If a bar-code system might solve some of your problems,
you need the detailed information in Assembling a BarCode Tracking System (0271–2834–MTDC). Technically
savvy users will be able to design and assemble a system
that meets their needs. Others will learn enough to work
with a system designer or vendor to acquire a system
that works for them. Assembling a Bar-Code Tracking
System may be ordered from MTDC, Attn: Publications
Distribution.
The authors wish to thank Aram Eramian, Allen Seelye,
Tony Sirchio, Steve Oravetz, and Longchaw Lee for
information and research that contributed to this report.
Electronic copies of this Tech Tip and Assembling a BarCode Tracking System are available to Forest Service
and Bureau of Land Management employees on the
Forest Service’s Intranet at: http://fsweb.mtdc.wo.fs.fed.
us/pubs/htmlpubs/htm02712333/
The following Web sites address general bar-coding
issues. Interested readers are encouraged to search
out other Internet sites that may address their specific
interests.
Additional Information
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http://www.adams1.com
Bar code 1 is an independent Web site devoted to everything bar coded. It contains links and short assessments
of equipment and software from many different suppliers.
http://www.aimusa.org
The Association for Automatic Identification and Data
Capture Technologies (AIM) is a global trade association.
About the Authors
Jasen Neese is an independent contractor who has
contributed to various projects at MTDC since receiving
his bachelor’s degree in natural resource conservation
in 2000 from the University of Montana. He served as
a student intern at MTDC from 1997 to 2000.
Kathleen Snodgrass joined MTDC as a project leader
in 2001. She came from the Nez Perce National Forest
where she was the facilities architect, and also worked
in landscape architecture, facilities, land line, and general
engineering. After graduating from Washington State
University in 1974 with a bachelor’s degree in architectural studies, she spent about 10 years in highway design
and construction with the Idaho Division of Highways.
http://www.barcodeunlimited.com
Barcodeunlimited.com is a site explaining the history
and technology of bar codes.
http://fsweb.r9.fs.fed.us/special/data_recorders/
index.shtml
This site is the Forest Service portable data recorder
teamroom.
Library Card
Neese, Jasen. Snodgrass, Kathleen. 2002. Bar-code tracking systems
overview. Tech Tip 0271-2333. Missoula, MT: U.S. Department of
Agriculture, Forest Service, Missoula Technology and Development
Center. 8 p.
Describes the basics of bar-code systems that can be used to maintain
inventories or track pesticides, equipment, tree-marking paint, or other
materials. Bar codes use a series of vertical black lines and spaces to
record data. The standard used to convert data to a bar code is called
a symbology. More than 250 symbologies are in use. Forest Service
users should consider using symbology code 128, the standard used
in the shipping industry. It can encode all 128 ASCII characters (lowercase and capital letters, numbers, punctuation marks, and other
symbols) and can be used to create high-, medium-, and low-density
bar codes. The label lines are closely spaced in high-density bar codes,
allowing more data to be stored, but the label might not be read as
reliably. Setup and the initial inventory entry are usually the most timeconsuming steps in establishing a bar-code system. A bar code might
represent the identification of a container of pesticide. Software, usually
some form of database, stores additional information about the container
of pesticide, such as when it was purchased, how much the container
holds, how much has been used, and when the container was disposed
of. The bar code would be placed on the pesticide container when it
was received. Each time some of the pesticide was used, a scanner
would record the bar code and the user would enter appropriate information about the use. Such a system would allow careful tracking of
the use of pesticides and the software would allow the user to prepare
periodic reports. This Tech Tip considers three sample uses of barcode systems by Forest Service employees: tracking tools, inventorying
chemicals and material safety data sheets, and reporting on pesticides.
An accompanying report, Assembling a Bar-Code Tracking System
(0271–2834–MTDC), has more detailed information that can be used
to design a bar-code system.
Keywords: chemicals, data collection, data recorders, hazardous
materials, hazmat, inventories, personal digital assistants,
pesticides, portable instruments, scanners, scanning, stocks,
symbology codes, tracking, wireless communications
Additional single copies of this document may be ordered from:
USDA FS, Missoula Technology and Development Center
5785 Hwy. 10 West
Missoula, MT 59808–9361
Phone: 406–329–3978
Fax: 406–329–3719
E-mail: wo_mtdc_pubs@fs.fed.us
Electronic copies of MTDC’S documents are available on the
Forest Service’s FSWeb Intranet at:
http://fsweb.mtdc.wo.fs.fed.us
The Forest Service, United States Department of Agriculture (USDA), has developed this information
for the guidance of its employees, its contractors, and its cooperating Federal and State agencies,
and is not responsible for the interpretation or use of this information by anyone except its own
employees. The use of trade, firm, or corporation names in this document is for the information and
convenience of the reader, and does not constitute an endorsement by the Department of any
product or service to the exclusion of others that may be suitable. The U.S. Department of Agriculture
(USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national
origin, sex, religion, age, disability, political beliefs, sexual orientation, or marital or family status. (Not
all prohibited bases apply to all programs.) Persons with disabilities who require alternative means
for communication of program information (Braille, large print, audiotape, etc.) should contact
USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination,
write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, 1400 Independence
Avenue, SW, Washington, D.C. 20250–9410, or call (202) 720-5964 (voice and TDD). USDA is an
equal opportunity provider and employer.
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For further technical information, contact Kathie Snodgrass at
MTDC.
Phone: 406–329–3922
Fax: 406–329–3719
E-mail: ksnodgrass@fs.fed.us